PEAK Swine Genetics clients are amongst the leaders in achieving high returns from their production units! These hog barn managers pay attention to details, they assure that hogs are weighed correctly for their slaughter market, they find slaughter markets that suit their management and breeding programs best, so as to gain the excellent returns that they do.

Boars and gilts probed at F & S Hog Farm in December continue to show terrific development in their performance. Biggest loin probed at 100 kg liveweight on Landrace was 66.3 mm and on Yorkshires was 67.7 mm.

Standing at the “top of the world” above Quito, Ecuador at 4100 metres elevation requires deep breaths because of the low oxygen level (although no O2 mask needed), compared to the 1400 metre high passes we have in our own British Columbia.

Sow Weight

The energy requirement for maintenance of the sow increases by about 160 g for every increase of 45 kg in sow weight. Therefore, any feeding system for gestating sows that ignores sow weight will be inaccurate. Most farms are not equipped or prepared to spend the time, effort or expense of weighing sows. Therefore, feeding tables have been developed based on visual estimates of sow weight or on sow weight calculated from flank to flank measurements obtained using a simple cloth tape measure.

Sow Backfat

Backfat level by itself is not a good predictor of sow performance. I am sure you have seen thin sows do very well and fat sows doing poorly.

Suggested target backfat levels for sows might be:

But backfat is a good indicator of the sow’s body reserves. The less backfat she has, the less reserves she has. So the margin of error in underfeeding her is very small. If a thin sow has to draw on her body reserves during lactation to support milk production, she will draw on her protein tissues to supply the energy she needs. If she mobilizes more than 12% of her protein stores during lactation, litter growth rate will be reduced and subsequent reproductive efficiency will also be reduced. Also, thin sows (<13 mm backfat) have lowered insulation against cold, much higher activity levels and spend more time standing rather than lying down. Therefore, their maintenance requirements are much higher than those of sows in good condition.

Thin sows of the same weight as sows in good condition require as much as 0.6 kg more feed per day, just to put on the same amount of weight. Also, thin sows are much more susceptible to shoulder sores. In contrast, sows with excessive amounts of backfat at farrowing (>20 mm) will have lower lactation feed intake. This leads to poorer subsequent reproductive performance and possibly early culling from the herd. Obviously, we need a feeding program that will ensure that all sows are neither too thin (<13 mm) nor too fat (>20 mm) at the time of farrowing.

Backfat Measurement

Sow backfat can be measured electronically using a Renco Lean Meater. These machines are durable, relatively inexpensive and easy to use after a little training. Backfat measurements are taken at the last rib, 7 to 9 cm (2.5 to 3.0 inches) off the midline of the sow. Measures are taken on both sides and the maximum value taken.

It is important to note that target backfat levels are not average herd values but are targets to be reached for every sow. A target value of 19 - 20 mm backfat allows for a loss of 3 - 4 mm backfat during lactation. It has been shown that sows with less than 14 mm backfat at weaning have lower reproductive performance.

In the next article we will present a table of feeding allowances for gestating sows based on an estimate of weight and backfat thickness at time of breeding.

[Part 6 will conclude the production and productivity recommendations from Dr. Frank Aherne, since his death on December 5, 2005. We deeply regret Dr. Aherne’s passing at 70 years of age. I am, however, most pleased that PEAK Swine Genetics was able to provide these timely and important barn references for you, from a world-renowned expert in swine productivity and production.]

Site Design:  Summit Solutions Ltd.